Process of producing alkali metal silicates in blast furmaces



l alkali metal present is o f I heretofore gases tends to UNITED STATES PATENT OFFICE.

No Drawing.

Specification of Letters Patent. Patented Aug. 8, 1922.

Application flied December 18, 1920. Serial No. 481,701. To all whom it may cmwem: bined losses are often quite serious, a they may g. at the total alkali involved, and they therefore in the county of Ohio and State constitute a considerable tax on the cost of of West irginia, have invented certain new the manufactured product. and useful Improvements in recesses of (cording to this invention, on the other Producing Alkali Metal Silicates in Blast hand, I make up a suitable charge of silica, urnaces; and I do ereby declare the folalkali metal compound and carbonaceous material, place the same in a blast furnace, and fire the same, whereupon I am enabled to produce an alkali metal silicate at a cost much lower than by any other process with which I am familiar. In other words, I have discovered that when quartz or other suitable form of silica admixed with sodium carbonate, sodium sulphate, etc., are charged into a cupola or blast furnace with cake in the usual manner of carrying out blast fur- IifilCGfOPGIiltlOIlS, the resulting t e tains to make and use the same.

is invention relates to a process of producing alkali metal silicates in a blast fur nace, and has-for its object to produce said, silicates in a manner less costly than has been proposed. Vith these and other objects in view the invention consists in the novel steps and combinations of steps constituting the process, all as will be more fully hereinafter disclosed and particularly pointed out in the claims. 7

In order that the precise invention may be c more clearly'understood, it is said: As

an acidic or such a basic nature as the charged mixture is proportioned to produce. That is to say, I have discovered that the percentage of sodium or potassium silicate is well known, the usual procedure in making found in the slag of blast and similar fursilicate of soda for the-,purposeof manufacnaces may be readily controlled by adding turing glass is to melt in a reverberatory furthe proper quantities of alkali metal comnace a suitable mixture of sodium carbonate pounds to the silica of the charge while operand sand, or other form of silica. ating said furnaces.

' I have further discovered that the loss of alkali metal present in the charge is surprisingly very small. In fact, I have found that the resulting slag will frequently contain as much as 99% of the total sodium or potassium charged into the furnace.

Accordingly, in carrying out the invention I add to the regular blast furnace a silicate charge containing such a percentage oxide which being volatile of sodium carbonate, sodium sulphate, or at the temperature employed escapes from of potassium salts, as w ll produce n the the"furnace with the gaseous products of, blast f slag the desired percentage of combustion and thus not only occasions a alkali metal and I operate the furnace 1n 1 8 of the alkali present but also changes theusual manner, tapping out the slag rethe composition of the melt. ciselly as if an ordinary charge had 11 In addition to this the temperature necesemp oyed. a sary to heat the mixture is often danger- In thus operatlng the furnace to make a ously near the subliming temperature of the slag of any desired percentage of sihcate of' a li metal compound used and anaddisoda for example,- the volatilization' of the. tional loss by sublimation occurs" from this sodium compounds is robably igreater than source. Again, the rapid flow of combustion 1n the use of a rever ratory mace, but increase b th of thes 'losses such volatilized sodiumcomp'ounds are conby maintaining a minimum partial pressure densed on the cold descending charge inthe of said volatized materials in the high temppe pa tof the furnace and returned to perature zone in the furnace. These comt e fusion acne. The condensed alkali 110 particles of solid fuel are sometimes carried bodily from the fire box, to the melting charge and thus-give trouble. Asa result of these objections, a small moportion of the metal cmnpounds thus returned to the fusion 'mind. However, a suitable charge may be zone of course, will be readily vaporized unproportioned as follows til they effect such concentration of said To 1000 pounds of silica SiO add 300 compounds that their partial pressures bepounds of coke. The coke and silica come very high. In fact, they will soon cient coke to melt the charig, or say 300 reach such a point of concentration that pounds of coke. The co and silica any further volatilization 1S precluded, should be in lumps. I have discovered that 40 whereupon the sodium or potassium presthe coke will not discolor the product, and ent may combine with the-silica to form an that the latter will be clear of fogs or alkali metal silicate which is tapped from cloudy patches which is an important adthe furnace from time to time, or continvantage of thisprocess.

uously, as may be desired. What I claim 1s:- 45

- I prefer to ad such molten alkali metal 1. The rocess of making an alkali metal silicate directly into water so as to granusilicate suitable for glass making purposes, late the same and effect the hydration therewhich consists in providing a mixture of of, but I may cool the slag thus produced in carbon, silica, and a colorless nonoxidizing pots or I may blow it up with air or steam alkali metal compound in proportions 5 as desired. After the slag has been thus adapted to produce the desired silicate,

treated, it is ready to be sold to the glass charging said mixture In a furnace of the manufacturers as a raw material for makblast ty-pe, ignitingthe charge, and withing various kinds of glass. drawing the slag produced, substantially In determining on the exact composition as described. 55

of a charge, of course, one must know the 2. The process of making a sodium siliparticular glass which is to be made from cate for glass making purposes in a blast the slag produced, and the particular refurnace, which consists in charging said quirements of the manufacturer who is to furnace with a mixture of silicauand carbon use it. The data varies with the manufacin ldmps to which has been added a color- 0 turer and also with the kind of glass, less non-oxidizing sodium compound ignitso that it is scarcely necessary to ing the charge to form the desired silicate give a specific example. Sufiice it to say in the form of a slag, and recovering said that any furnace man or glass maker slag, substantiall as described.

would readily proportion the ingredients to In testimony whereof I afiix my signature. as the particular purpose which'he had in SAMUEL PEACOCK.

Certificate of Correction.

It is hereby certified that in Letters Patent No. 1,425,048, granted August 8, 1922, upon the application of Samuel Peacock, of Wheeling, West Virginia, for an improvemant in Processes of Producing A1kali-Metal Silicates in Blast Furis, an error appeans in the printed specification requiring correction as follows: Page 2, strike outlines as, 31, and as and 158m ma To 1000 M of silica, $10,, add :00 pound; of dam oan'de 1%,0, and mm: cake to melt on charge, or 8031 300, and that the said Letters Patent should be toad with this ourmotion therein that tho sam'e may conform to the mcord of the case in tho Patent Oflice.

Signed and sealed this 3d day of October, A. D., 1922.

WE. A. KINNAN,

Assistant C'onma'uimier of PM. 

